Ok on a motor home. if it has "drive shaft parking brake" then having one rear wheel off the ground is not a good thing... One Front is OK
Do not have both --either end--off the ground,.
if it has wheel applied parking brakes. You are good.
Suggestion. Carry a few plank. one (or two if it's duals) 3 or 4 feet long
two more about half that length and again two more 1' They should be at least the width of the tires
Mine are 2x12's 3' 2' and 1' long (Tires are 8" so I also have some 2x8 assemblies 3' on top of that is glued a 2' and on top fo that a 1)
PUll onto the plank to "pre-level" that corner then use the jacks. YOu will stil have good "engagement"
if you are already parked. Consider a 12 ton (or 20) Air/hydrauilc jack from harbor freight and oh say 6 gaLLON 150 PSI TANK TYPE COMPRESOR.. pICK THE WHEEL UP AND SHOVE THE PLANKS UNDER. DROP DOWN. gOOD.
hAd one 5er owner having the devil's own time positing on his leeling boards. Finally told him "Get it level and then we will position the boards. I can only pick up 12 ton (You can imagine the look I got) Loaded the compressor and hack in the wagon and pulled it over.. and .. I can only pick up 12 tons.